This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Aggregatibacter actinomycetemcomitans (Aa) is a gram negative capnophilic oral bacteria and the putative cause of Localized Aggressive Periodontitis (LAP) in preteens and teenagers. It has been shown in vitro to colonize buccal epithelial cells of humans and old world monkeys exclusively. This attachment is mediated by bacterial surface proteins, aae and apiA which are receptors which attach to ligands on the buccal epithelial cell membrane. Further, the buccal epithelium appears to be a primary reservoir of Aa in humans. The purpose of this study is to determine the earliest patterns of oral colonization of Aa in the primate mouth and determine the roles of apiA and aae in the pattern of colonization. Monkeys are screened with oral swabs and dental plaque scraping for presence of Aa bacteria and the strain of bacteria identified with novel PCR assays. Additionally, a smaller group of monkeys is inoculated with Aa bacteria following disinfection of the oral cavity with antiseptic solution. Inoculation of various strains including knockout and antibiotic resistant strains will help to determine the host range for Aa bacteria and the use of a nonhuman primate model fo the human disease.